How do we know Jesus didn't have any other siblings? I was reading the Bible and I read the chapter Jesus' Mother and Brothers, Mark 3:31-35, it says "Then Jesus' mother and brothers arrived. Standing outside, they sent someone in to call him. A crowd was sitting around him, and they told him, 'Your mothers and brothers are outside looking for you.' 'Who are my mother and brothers?' He asked. Then he looked at those seated in a circle around him and said, 'Here are my mother and brothers! Whoever does God's will is my brother and sister and mother.'" First of all the chapter is called Jesus' mother and brothers, why would they call it that when they could say Jesus' mother and disciples? Or is it called that because Jesus says everyone there is his brothers and mothers, and it's named after them. Also, Jesus tells them that everyone who does God's will is his brother or sister after they call those people his brothers. So why would Jesus say that the others were his brothers and sisters when, if they called those people his brothers, but they weren't, they must believe that others can be his brothers without having the same blood. So if that's true, Jesus is teaching them a lesson they already know. Obviously by them saying that those men are his brothers, they must know that those are his actual brothers, if Jesus teaches them that the people who aren't his blood relatives can be his brothers, that means that they must not have believed that and thought that only they were his brothers because they were his brothers by blood. Sorry this is kind of confusing, it's hard to put these thoughts into words, hopefully you can understand this. I am fine with the teaching, and I believe it if the church does, it's just I want to know where we get the information supporting our belief that Mary didn't have other children, and I want to understand it as much as possible, so then I can come to truly believe it and not have any doubts. This chapter has definitely made me think about this belief, and I'd like to know what you guys think.